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iosobjective-ccalendarekeventekeventkit

EKEvent <!ExceptionDate!> vs RID

I have iOS application(written on objective c) which works with events from the calendar. Something strange that I saw is on change of recurrent meeting is that in the most of the cases the calendarItemExternalIdentifier field was changed and there is /RID=XXXXXXX part is added but in some of the cases I receive same calendarItemExternalIdentifier with 20161205 added at the end.

For example I have external identifiers like this:

[email protected]

And on change I can receive this:

[email protected]/RID=505299600

or this:

[email protected]<!ExceptionDate!>20161205

Why we have this and what is the difference?

Solution

  • As far as I figured out (while on search for an answer for this, too)< the difference relies on which calendar type you are using.

    Exchange Calendar events use /RID=, where the Timestamp is the time interval since 00:00:00 UTC on 1 January 2001 to the new Date.

    while

    Local Calendar (and I think CalDAV Calendars - I'll check this later) use